Antiperspirants and Alzheimer's Disease. Back in the 1960s, a few studies found high levels of aluminum in the brains of people with Alzheimer's disease. The research suddenly called into question the safety of everyday household items such as aluminum cans, antacids, and antiperspirants.
A harmonic drive apparatus comprises a circular spline which has internal spline teeth and which is rotatable around a rotational axis , a flexible cylindrical flexspline which is concentrically disposed within the circular spline and which has external spline teeth , the number of flexspline external teeth being less than the number of internal ...
The harmonic mean is a better average when the numbers are defined in relation to some unit. The common example is averaging speed. For example, suppose that you have four 10 km segments to your automobile trip. You drive your car: 1  100 km/hr for the first 10 km. 2  110 km/hr for the second 10 km.